Consider topics that are important, as they'll only help you to score more. Here's few of them

* Physics

Work , Energy, Power

Current Electricity

Wave and Ray optics

Modern and Nuclear Physics

Wave and String Motion

* Maths

Circles

Vector

PnC and Probability

A.O.D

Integration

Sequence and Series

* Chemistry

p, s, d & f block elements

Atomic structure

Chemical bonding

Organic Chemistry

Hello Tanu,

So let me start by physics for JEE MAIN

LOW EFFORT REQUIRED & HIGH WEIGHTAGE

• Heat & Thermodynamics             
• Ray Optics          
• Electromagnetic Waves
• Semiconductors
• Error & Instrument Analysis       
• Gravitation        
• Wave Optics      
• Photoelectric Effect       
• Oscillations     

Now let me tell you about chemistry

LOW EFFORT REQUIRED & HIGH WEIGHTAGE

•  Atomic Structure             
• Gaseous & Liquid State
• Electrochemistry             
• Chemical Kinetics            
• Nuclear & Surface Chemistry     
• Chemical Bonding           
• d-Block Elements            
• Co-ordination Compound            
• Alkyl Halides      
• Aromatic Compounds

Now coming to mathematics

LOW EFFORT REQUIRED AND HIGH WEIGHTAGE

• 3 Dimensional Geometry
• Vectors
• Determinant & Matrices
• Sequence & Series
• Straight Line
• Circle
• Probability Distribution (Binomial + Mean & Variance)

I would still tell you that do other topic as well so that you score very well.

I hope this answer helps you and all the very best to you!